UV-LED irradiation technology for point-of-use water disinfection in developing communities

Ultraviolet (UV) irradiation is a common disinfection option for water treatment in the developed world. There are a few systems installed in developing countries for point-of-use treatment, but the low-pressure mercury lamps currently used as the UV irradiation source, have a number of sustainability issues including a short lifetime of approximately one year and toxic mercury inside that must be disposed of after they are used. UV light emitting diodes (LEDs) may present solutions to many of the sustainability issues presented by current UV systems. LEDs are small, efficient, have long lifetimes, and do not contain mercury. LEDs have recently become available in the germicidal wavelength range and this research assessed their efficiency for inactivation of E. coli in water compared to low-pressure lamps. A UV-LED prototype was also evaluated as a proof-of-concept of this technology for a point-of-use disinfection option.

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